China
Africa
Explore chapters and articles related to this topic
Developmental Disorders
Published in Jeremy R. Jass, Understanding Pathology, 2020
Congenital malformations have been known to humankind since the dawn of time. Serious malformations are due to a localised error of structural development occurring in the eight weeks following conception. Milder defects (included in Table 10) develop later. One malformation may lead to another and be caused by genetic factors, by environmental factors or by a combination of the two. The genetic causes are classified into chromosomal and single gene disorders. A chromosomal disorder implies an abnormality that can be visualised by the technique of preparing a chromosome spread from a dividing cell and examining the stained chromosomes under a microscope (karyotyping). Abnormalities may include an extra chromosome (e.g. trisomy 21 causing Down’s syndrome), an absent chromosome (e.g. XO causing Turner’s syndrome), deletion of part of a chromosome, inversion of part of a chromosome or a translocation of one part of a chromosome to another. Chromosomal disorders usually arise during gametogenesis and are generally not transmitted since affected individuals either die at birth or are sterile.
Fetal Structural Malformations and Recurrent Pregnancy Loss
Published in Howard J.A. Carp, Recurrent Pregnancy Loss, 2020
Howard J.A. Carp, Thomas Philipp, Micha Baum, Michal Berkenstadt
It is unlikely that maternal factors such as antiphospholipid antibodies, thrombophilic disorders, endocrine factors, or uterine anomalies cause the developmental defects observed embryoscopically. After exclusion of a chromosomal disorder, these developmental defects might be heterogenous in their origin. Recent studies using molecular techniques, such as NGS or whole exome sequencing (WES), have shown that imbalances in genes required for embryonic growth and morphogenesis and mutations exist in karyotypically apparently normal spontaneous miscarriages, malformed fetuses, and embryos with developmental abnormalities documented by embryoscopy [18].
Prenatal diagnosis, antenatal screening and reproductive aspects of medical genetics
Published in Angus Clarke, Alex Murray, Julian Sampson, Harper's Practical Genetic Counselling, 2019
The recurrence risks for the major types of chromosome disorder are discussed in Chapter 4, and the strength of indication for prenatal diagnosis will depend on the magnitude of this risk as well as on the nature of the disorder and the attitude and experience of the couple concerned in relation to it. The relative risks of amniocentesis and CVS will need careful consideration, especially where the risk of abnormality in the pregnancy is low. The main chromosomal indications for prenatal diagnosis are considered individually later in this chapter (see also Box 9.3).
Value of Placental Examination in the Diagnostic Evaluation of Stillbirth
Published in Fetal and Pediatric Pathology, 2022
The fetal causes (14/147 cases, 9%) encompassed chromosomal and non-chromosomal malformations which included those of the central nervous system (hydrocephalus, type II Chiari malformation, vein of Galen aneurysmal dilation), McKusick-Kaufman syndrome, lethal polymalformative syndrome associated with chromosomal aberration (trisomy 18, two cases) or strongly suspected to be chromosomal disorder (not cytogenetically investigated, eight fetuses, 5%) because of the characteristic placental histologic features of aneuploidy. The aneuploid placental villi displayed an important immaturity with a thickened layer of trophoblast and hypovascular reticular stroma. Their contours were typically very irregular delineating deep invaginations, and their stromal axis showed central cystic spaces and pseudo-rosettes.
Turner syndrome and autosomal dominant polycystic kidney disease
Published in Baylor University Medical Center Proceedings, 2021
Rachel Styer, Matthew Stephen, Faris Hashim, Krista Birkemeier
Turner syndrome (TS) is a sex chromosome disorder resulting from the complete or partial loss of one of the X chromosomes.1,2 This syndrome affects approximately 1 in 2000 to 5000 females.1 The genetic anomaly results in multisystem disease, which may include malformations of the reproductive, cardiac, integumentary, renovascular, and endocrine systems, among others. Short stature is one of the most common features of TS3 and is commonly treated with growth hormone (GH) with favorable increases in achieved height.2 In addition to growth promotion, GH plays a role in regulating the functions of many organs, including the kidneys.4 Autosomal dominant polycystic kidney disease (ADPKD) affects approximately 1 in 500 people worldwide.5 It is a multisystem disease that characteristically has bilateral renal cysts and an increased risk of intracranial aneurysms, among other manifestations. ADPKD is also an important cause of end-stage renal disease, which affects about half the patients with ADPKD.5
Twin pregnancy with chromosomal abnormalities mimicking a gestational trophoblastic disorder and coexistent foetus on ultrasound
Published in Journal of Obstetrics and Gynaecology, 2018
Akiko Ohwaki, Haruki Nishizawa, Noriko Aida, Takema Kato, Asuka Kambayashi, Jun Miyazaki, Mayuko Ito, Makoto Urano, Yuka Kiriyama, Makoto Kuroda, Masahiro Nakayama, Shin-Ichi Sonta, Kaoru Suzumori, Takao Sekiya, Hiroki Kurahashi, Takuma Fujii
We recommend careful performance of the differential diagnosis of abnormal placenta with snowstorm pattern, particularly in cases with a coexistent foetus. A molecular cytogenetic study including zygosity test is necessary for differential diagnosis because it is possible that a chromosomal disorder might underlie placental abnormalities. The severities of the clinical symptoms in the foetus with such disorders vary widely. These disorders often result in lethality from multiple congenital anomalies, whereas cases with milder cytogenetic abnormalities can occasionally survive and live to a good age. Furthermore, confined placental mosaicism might affect the foetus to a lesser degree (Johnson and Wapner 1997; Lestou and Kalousek 1998). Thus, the results of the cytogenetic test might seriously affect the choice of treatment for the ultrasound findings.